[llvm] [OFFLOAD][L0] Add wait events for AsyncQueue memFill (PR #202287)

[Nick Sarnie via llvm-commits]

================
@@ -252,9 +252,11 @@ Error L0AsyncQueueTy::memoryFillImpl(void *Ptr, const void *Pattern,
   auto EventOrErr = Device.getEvent();
   if (!EventOrErr)
     return EventOrErr.takeError();
+  auto [numWaitEvents, waitEventsPtr] = getMemCopyEvents();
----------------
sarnex wrote:

```suggestion
  auto [NumWaitEvents, WaitEventsPtr] = getMemCopyEvents();
```

https://github.com/llvm/llvm-project/pull/202287